On April 17, 2024, Tortolita Alliance (TA) filed a Public Records Request (PRR) with the Arizona State Land Department (ASLD) for "all ASLD internal and external communications with the Town of Marana (including ASLD full-time and part-time employees & consultants) from 1/1/20 to 4/17/24. This would include all emails, letters, meeting notes, maps, studies and reports related to the Tortolita Preserve and surrounding lands." After many follow-up requests and assistance from the Arizona Ombudsman, TA finally received two records productions from ASLD on 9/5/24 and 9/25/24.
One of the most astonishing documents received in the second records production was a study/report commissioned by ASLD entitled, I-10 Tangerine Marana Area Drainage Master Plan Report-11/21/18 & Revised 6/17/19 by JE Fuller/Hydrology and Geomorphology, Inc. (Report). The Study Area is the Tortolita Fan (large alluvial fan) as shown in Figure 1 above.
The name of the Report is deceiving because it was more than a drainage study. As stated in the Executive Summary, "The purpose of this study is to present a concept land-use plan with the goal of promoting future development within State-owned property".
You can download the entire report at this link:
The following presents key information found in the Report and compares it to information we received in October 2019 when the Town of Marana (Marana) announced the proposed reconfiguration and re-zoning of the Tortolita Preserve. You may well be outraged.
The Report included these key elements; (1) Hydrology, (2) Hydraulics, (3) Drainage Corridors, (4) Sediment Analysis/Detention Basins, (4) Development Areas and (5) Construction Cost.
Hydrology
Hydrology is the analysis of rainfall and runoff coming from the 10 sub-watersheds (see Figure 2-left) upstream of the Tortolita Fan for the 100-year flood event. Hydrology models were utilized to establish the peak flows coming from each watershed.
Hydraulics
Hydraulics model analysis routes the peak flows through the study area to show maximum flood depths for the 100-year flood event. Figure 5 (right) shows the results color-coded by depth. Much of the Tortolita Fan has flood depths of 0.5 feet to 2.0 feet. Note the flooding that occurs at the I-10 area where the stormwater accumulates!
Drainage Corridors
The Hydraulics information was then utilized to establish proposed floodway corridors that would be channelized to transport water downstream. These are the light green areas shown on Figure 15. The areas outside the flood corridors were proposed for development as described below.
Sediment Analysis/Detention Basins
When flooding occurs in desert regions sediment moves easily. Also, detention basins are required to regulate the flows in order to temper the peaks. Accordingly, four detention basins were proposed to detain water and trap the sediment.
I have professional experience with stormwater flows in desert regions. Take a look at this video showing an actual 50-year storm in the alluvial fan of the Little San Bernardino Mountains in Thousand Palms, CA to give you a visual of the power of water and sediment transport. And this was only a 50-year storm event! Any attempt to channelize and detain 100-year storm flows in the Tortolita Fan is unwise. In fact, the 100-year storm design standard is probably now obsolete with the temperature and precipitation extremes now experienced throughout the nation, e.g., recent North Carolina flood damage. The Tortolita Fan should be left undisturbed to dissipate stormwater flows naturally.
Development Areas
Fuller then established 29 potential development areas located outside the proposed drainage corridors. See light blue areas in Figure 29 below.
This proposal would obliterate the Tortolita Fan!
Stormwater Facility Construction Cost
The Report included the construction cost for just the regional stormwater facilities which include armored banks along the drainage corridors, detention basins and a diversion channel.
The estimated cost for stormwater facilities alone is $708 million! Incredible!
The Deception
I moved to my new home in Dove Mountain in July 2019. Prior to purchase, I was assured by Marana that the Tortolita Preserve would be there for at least 99-years.
After we moved in, I read the draft Make Marana 2040 General Plan and noticed that the Tortolita Preserve had been removed from the maps and replaced with a new zoning component. This prompted my 8/12/19 letter to Marana questioning what happened to Tortolita Preserve and other issues. That letter was circulated around Dove Mountain and peaked the interest of many residents.
On 10/7/19, Marana held a Dove Mountain community meeting at the Highlands and announced the Tortolita Preserve was going to be reconfigured and rezoned as part of the Make Marana 2040 General Plan. The community was shocked.
We were provided the following Map showing the reconfiguration. It really didn't make much sense at the time but you will note this Map looks very similar to Figures 14 and 15 from the Report shown above. This Map shows the exact same floodway corridors as presented in the Report but depicted in solid green. The Tortolita Preserve is shown in hatched green.
However, Marana nor ASLD never mentioned nor referenced the Report!
After this, a small group of us gathered and provided presentations to the Highlands and Del Webb Dove Mountain HOAs. The Tortolita Alliance was born!
Next the residents of Dove Mountain rallied and hundreds attended Planning Commission Meetings and Town Council Meetings and Marana wisely put an end to the reconfiguration and rezoning of the Tortolita Preserve.
Now (5 years later) we find out through a PRR that there was much more behind the Map provided to us. They deceived the public by presenting only this Map when knowing full well they were planning to develop the entire Tortolita Fan----despite the stormwater challenges and the nearly $1 billion cost and the fact there is no municipal water supply for this area.
Fortunately, it appears that ASLD has suspended this cockamamie scheme but we must be ever vigilant.
We also know that a local developer was actually employed by ASLD at the time and was a part of this scheme and it is quite possible that same developer is still trying to develop the Tortolita Fan.